Cannot set password for user with adduser

Recently with my Banana Pi M3 I was having multiple issues while installing. One of them was an error message when trying to set up a new user. See the error message below.

Current password:
New password:
New password (again):
passwd: Authentication token manipulation error
passwd: password unchanged

Smyptoms

When adding a new user with

sudo adduser $user

The system does not accept a password and produces the above message.

Solution

I have found that removing the (non existing ?) password from the user is the only way to solve the problem quickly. It is a weird thing, I have no clue what is causing this.

While logged in as any user with root privileges (sudo), delete the $user password,

sudo passwd -d $user

And set a new password for $user,

sudo passwd $user

It should work now.

Credit goes to Askubuntu.com. Thanks!